High Lockout
09 on Glow-worm Xtramax HE

Your boiler has lost its ability to monitor water pressure because the internal sensor has developed an electrical fault.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

LOSS OF WATER PRESSURE SENSOR: SENSOR IN SHORT CIRCUIT OR HAS ISOLATION FAULT. CHECK THE ELECTRICAL CONNECTIONS.

What causes this fault?

This fault occurs when the boiler's internal computer can no longer read the water pressure because the sensor's electrical circuit has failed. The most common reason is that the sensor has either suffered an internal short circuit or the connecting wires have become loose or damaged over time.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

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